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Lost acceleration while driving.

Today while driving, I experienced a very sudden loss of acceleration. I attempted to press the accelerator with no response at all. After pulling off the road, the engine died as I came to a stop. I attempted to start the engine, but it would only turn over, i only got it to start once in the hour that I was waiting for a tow, it ran for about 20 seconds before dying again. The engine will turn over, but will not start. After getting it home, I removed and cleaned the MAF sensor with MAf sensor cleaner, let it dry, and reinstalled it. This seemed to fix the issue, as the engine fired up like normal on the first attempt. About an hour later I went to start it again, only to find it turning over , and not starting, in the same manner as when the engine initially died. As far as I can tell, it isnt a battery issue as I still have power to everything. My questions are, has anyone seen this before?, what could be causing this?, and what is the best cousre of action to fix the issue? For reference it is a 2005 SR5, with 192K miles on the 4.7L V8.

From the outside looking in and with no experience with those specific engines, it sounds like a fuel delivery issue. I had a Nissan that would do like that and it was due to a clogged fuel filter and the fuel pump dying a slow death. With the ignition switched on for long enough, the fuel pump would prime and eventually build enough pressure to start the engine, but it couldn't maintain adequate pressure to keep the truck running.

Hopefully others with more experience with this engine chime in soon, but if you choose to investigate the fuel delivery start at the injectors and work your way back.

Quote:

Originally Posted by boomtown757 (Post 3308013)

Has the timing belt been replaced recently?

If so one other member had a very similar if not an exact experience, his problem ended up being the wire/s for a cam position sensor was routed incorrectly when the timing belt was replaced and had been rubbing on a pulley or something else and wore through grounding out the wire/s, once he isolated it and repaired the wire all was fine.